/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.confignode.procedure.impl.schema;

import org.apache.iotdb.common.rpc.thrift.TConsensusGroupId;
import org.apache.iotdb.common.rpc.thrift.TDataNodeLocation;
import org.apache.iotdb.common.rpc.thrift.TRegionReplicaSet;
import org.apache.iotdb.common.rpc.thrift.TSStatus;
import org.apache.iotdb.commons.exception.IoTDBException;
import org.apache.iotdb.commons.exception.MetadataException;
import org.apache.iotdb.commons.path.PartialPath;
import org.apache.iotdb.commons.path.PathDeserializeUtil;
import org.apache.iotdb.commons.path.PathPatternTree;
import org.apache.iotdb.confignode.client.DataNodeRequestType;
import org.apache.iotdb.confignode.client.async.AsyncDataNodeClientPool;
import org.apache.iotdb.confignode.client.async.handlers.AsyncClientHandler;
import org.apache.iotdb.confignode.procedure.env.ConfigNodeProcedureEnv;
import org.apache.iotdb.confignode.procedure.exception.ProcedureException;
import org.apache.iotdb.confignode.procedure.exception.ProcedureSuspendedException;
import org.apache.iotdb.confignode.procedure.exception.ProcedureYieldException;
import org.apache.iotdb.confignode.procedure.impl.statemachine.StateMachineProcedure;
import org.apache.iotdb.confignode.procedure.state.schema.DeactivateTemplateState;
import org.apache.iotdb.confignode.procedure.store.ProcedureType;
import org.apache.iotdb.db.metadata.template.Template;
import org.apache.iotdb.mpp.rpc.thrift.*;
import org.apache.iotdb.rpc.TSStatusCode;
import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.*;
import java.util.stream.Collectors;

public class DeactivateTemplateProcedure
        extends StateMachineProcedure<ConfigNodeProcedureEnv, DeactivateTemplateState> {

    private static final Logger LOGGER = LoggerFactory.getLogger(DeactivateTemplateProcedure.class);

    private String queryId;
    private Map<PartialPath, List<Template>> templateSetInfo;

    private transient String requestMessage;
    // generate from templateSetInfo by concat pattern and measurement in template
    private transient PathPatternTree timeSeriesPatternTree;
    private transient ByteBuffer timeSeriesPatternTreeBytes;
    private transient Map<String, List<Integer>> dataNodeRequest;

    public DeactivateTemplateProcedure() {
        super();
    }

    public DeactivateTemplateProcedure(
            String queryId, Map<PartialPath, List<Template>> templateSetInfo) {
        super();
        this.queryId = queryId;
        setTemplateSetInfo(templateSetInfo);
    }

    @Override
    protected Flow executeFromState(ConfigNodeProcedureEnv env, DeactivateTemplateState state)
            throws ProcedureSuspendedException, ProcedureYieldException, InterruptedException {
        long startTime = System.currentTimeMillis();
        try {
            switch (state) {
                case CONSTRUCT_BLACK_LIST:
                    LOGGER.info("Construct schema black list with template {}", requestMessage);
                    if (constructBlackList(env) > 0) {
                        setNextState(DeactivateTemplateState.CLEAN_DATANODE_SCHEMA_CACHE);
                        break;
                    } else {
                        setFailure(
                                new ProcedureException(
                                        new IoTDBException(
                                                "Target schema Template is not activated on any path matched by given path pattern",
                                                TSStatusCode.TEMPLATE_NOT_ACTIVATED.getStatusCode())));
                        return Flow.NO_MORE_STATE;
                    }
                case CLEAN_DATANODE_SCHEMA_CACHE:
                    LOGGER.info("Invalidate cache of template timeseries {}", requestMessage);
                    invalidateCache(env);
                    break;
                case DELETE_DATA:
                    LOGGER.info("Delete data of template timeseries {}", requestMessage);
                    deleteData(env);
                    break;
                case DEACTIVATE_TEMPLATE:
                    LOGGER.info("Deactivate template of {}", requestMessage);
                    deactivateTemplate(env);
                    return Flow.NO_MORE_STATE;
                default:
                    setFailure(new ProcedureException("Unrecognized state " + state.toString()));
                    return Flow.NO_MORE_STATE;
            }
            return Flow.HAS_MORE_STATE;
        } finally {
            LOGGER.info(
                    String.format(
                            "DeactivateTemplate-[%s] costs %sms",
                            state.toString(), (System.currentTimeMillis() - startTime)));
        }
    }

    // return the total num of timeseries in schema black list
    private long constructBlackList(ConfigNodeProcedureEnv env) {
        Map<TConsensusGroupId, TRegionReplicaSet> targetSchemaRegionGroup =
                env.getConfigManager().getRelatedSchemaRegionGroup(timeSeriesPatternTree);
        if (targetSchemaRegionGroup.isEmpty()) {
            return 0;
        }
        DeactivateTemplateRegionTask<TSStatus> constructBlackListTask =
                new DeactivateTemplateRegionTask<TSStatus>(
                        "construct schema black list", env, targetSchemaRegionGroup) {
                    @Override
                    protected Map<Integer, TSStatus> sendRequest(
                            TDataNodeLocation dataNodeLocation, List<TConsensusGroupId> consensusGroupIdList) {
                        // construct request and send
                        Map<Integer, TDataNodeLocation> dataNodeLocationMap = new HashMap<>();
                        dataNodeLocationMap.put(dataNodeLocation.getDataNodeId(), dataNodeLocation);

                        AsyncClientHandler<TConstructSchemaBlackListWithTemplateReq, TSStatus> clientHandler =
                                new AsyncClientHandler<>(
                                        DataNodeRequestType.CONSTRUCT_SCHEMA_BLACK_LIST_WITH_TEMPLATE,
                                        new TConstructSchemaBlackListWithTemplateReq(
                                                consensusGroupIdList, dataNodeRequest),
                                        dataNodeLocationMap);
                        AsyncDataNodeClientPool.getInstance()
                                .sendAsyncRequestToDataNodeWithRetry(clientHandler);
                        clientHandler
                                .getResponseMap()
                                .forEach(
                                        (k, v) -> {
                                            if (v.getCode() == TSStatusCode.SUCCESS_STATUS.getStatusCode()) {
                                                saveDataNodeResponse(k, v);
                                            }
                                        });
                        return clientHandler.getResponseMap();
                    }
                };
        constructBlackListTask.execute();

        if (isFailed()) {
            return 0;
        }

        long preDeletedNum = 0;
        for (List<TSStatus> respList : constructBlackListTask.getResponseMap().values()) {
            for (TSStatus resp : respList) {
                preDeletedNum += Long.parseLong(resp.getMessage());
            }
        }
        return preDeletedNum;
    }

    private void invalidateCache(ConfigNodeProcedureEnv env) {
        Map<Integer, TDataNodeLocation> dataNodeLocationMap =
                env.getConfigManager().getNodeManager().getRegisteredDataNodeLocations();
        AsyncClientHandler<TInvalidateMatchedSchemaCacheReq, TSStatus> clientHandler =
                new AsyncClientHandler<>(
                        DataNodeRequestType.INVALIDATE_MATCHED_SCHEMA_CACHE,
                        new TInvalidateMatchedSchemaCacheReq(timeSeriesPatternTreeBytes),
                        dataNodeLocationMap);
        AsyncDataNodeClientPool.getInstance().sendAsyncRequestToDataNodeWithRetry(clientHandler);
        Map<Integer, TSStatus> statusMap = clientHandler.getResponseMap();
        for (TSStatus status : statusMap.values()) {
            // all dataNodes must clear the related schema cache
            if (status.getCode() != TSStatusCode.SUCCESS_STATUS.getStatusCode()) {
                LOGGER.error("Failed to invalidate schema cache of template timeseries {}", requestMessage);
                setFailure(new ProcedureException(new MetadataException("Invalidate schema cache failed")));
                return;
            }
        }

        setNextState(DeactivateTemplateState.DELETE_DATA);
    }

    private void deleteData(ConfigNodeProcedureEnv env) {

        Map<TConsensusGroupId, TRegionReplicaSet> relatedDataRegionGroup =
                env.getConfigManager().getRelatedDataRegionGroup(timeSeriesPatternTree);

        // target timeseries has no data
        if (relatedDataRegionGroup.isEmpty()) {
            setNextState(DeactivateTemplateState.DEACTIVATE_TEMPLATE);
            return;
        }

        DeactivateTemplateRegionTask<TSStatus> deleteDataTask =
                new DeactivateTemplateRegionTask<TSStatus>(
                        "delete data", env, relatedDataRegionGroup, true) {
                    @Override
                    protected Map<Integer, TSStatus> sendRequest(
                            TDataNodeLocation dataNodeLocation, List<TConsensusGroupId> consensusGroupIdList) {
                        Map<Integer, TDataNodeLocation> dataNodeLocationMap = new HashMap<>();
                        dataNodeLocationMap.put(dataNodeLocation.getDataNodeId(), dataNodeLocation);
                        AsyncClientHandler<TDeleteDataForDeleteSchemaReq, TSStatus> clientHandler =
                                new AsyncClientHandler<>(
                                        DataNodeRequestType.DELETE_DATA_FOR_DELETE_SCHEMA,
                                        new TDeleteDataForDeleteSchemaReq(
                                                new ArrayList<>(consensusGroupIdList), timeSeriesPatternTreeBytes),
                                        dataNodeLocationMap);
                        AsyncDataNodeClientPool.getInstance()
                                .sendAsyncRequestToDataNodeWithRetry(clientHandler);
                        clientHandler
                                .getResponseMap()
                                .forEach(
                                        (k, v) -> {
                                            if (v.getCode() == TSStatusCode.SUCCESS_STATUS.getStatusCode()) {
                                                saveDataNodeResponse(k, v);
                                            }
                                        });
                        return clientHandler.getResponseMap();
                    }
                };
        deleteDataTask.execute();
        setNextState(DeactivateTemplateState.DEACTIVATE_TEMPLATE);
    }

    private void deactivateTemplate(ConfigNodeProcedureEnv env) {
        DeactivateTemplateRegionTask<TSStatus> deleteTimeSeriesTask =
                new DeactivateTemplateRegionTask<TSStatus>(
                        "deactivate template schema",
                        env,
                        env.getConfigManager().getRelatedSchemaRegionGroup(timeSeriesPatternTree)) {
                    @Override
                    protected Map<Integer, TSStatus> sendRequest(
                            TDataNodeLocation dataNodeLocation, List<TConsensusGroupId> consensusGroupIdList) {
                        Map<Integer, TDataNodeLocation> dataNodeLocationMap = new HashMap<>();
                        dataNodeLocationMap.put(dataNodeLocation.getDataNodeId(), dataNodeLocation);
                        AsyncClientHandler<TDeactivateTemplateReq, TSStatus> clientHandler =
                                new AsyncClientHandler<>(
                                        DataNodeRequestType.DEACTIVATE_TEMPLATE,
                                        new TDeactivateTemplateReq(consensusGroupIdList, dataNodeRequest),
                                        dataNodeLocationMap);
                        AsyncDataNodeClientPool.getInstance()
                                .sendAsyncRequestToDataNodeWithRetry(clientHandler);
                        clientHandler
                                .getResponseMap()
                                .forEach(
                                        (k, v) -> {
                                            if (v.getCode() == TSStatusCode.SUCCESS_STATUS.getStatusCode()) {
                                                saveDataNodeResponse(k, v);
                                            }
                                        });
                        return clientHandler.getResponseMap();
                    }
                };
        deleteTimeSeriesTask.execute();
    }

    @Override
    protected void rollbackState(
            ConfigNodeProcedureEnv env, DeactivateTemplateState deactivateTemplateState)
            throws IOException, InterruptedException, ProcedureException {
        DeactivateTemplateRegionTask<TSStatus> rollbackStateTask =
                new DeactivateTemplateRegionTask<TSStatus>(
                        "roll back schema black list",
                        env,
                        env.getConfigManager().getRelatedSchemaRegionGroup(timeSeriesPatternTree)) {
                    @Override
                    protected Map<Integer, TSStatus> sendRequest(
                            TDataNodeLocation dataNodeLocation, List<TConsensusGroupId> consensusGroupIdList) {
                        Map<Integer, TDataNodeLocation> dataNodeLocationMap = new HashMap<>();
                        dataNodeLocationMap.put(dataNodeLocation.getDataNodeId(), dataNodeLocation);
                        AsyncClientHandler<TRollbackSchemaBlackListWithTemplateReq, TSStatus> clientHandler =
                                new AsyncClientHandler<>(
                                        DataNodeRequestType.ROLLBACK_SCHEMA_BLACK_LIST_WITH_TEMPLATE,
                                        new TRollbackSchemaBlackListWithTemplateReq(
                                                consensusGroupIdList, dataNodeRequest),
                                        dataNodeLocationMap);
                        AsyncDataNodeClientPool.getInstance()
                                .sendAsyncRequestToDataNodeWithRetry(clientHandler);
                        clientHandler
                                .getResponseMap()
                                .forEach(
                                        (k, v) -> {
                                            if (v.getCode() == TSStatusCode.SUCCESS_STATUS.getStatusCode()) {
                                                saveDataNodeResponse(k, v);
                                            }
                                        });
                        return clientHandler.getResponseMap();
                    }
                };
        rollbackStateTask.execute();
    }

    @Override
    protected boolean isRollbackSupported(DeactivateTemplateState deactivateTemplateState) {
        return true;
    }

    @Override
    protected DeactivateTemplateState getState(int stateId) {
        return DeactivateTemplateState.values()[stateId];
    }

    @Override
    protected int getStateId(DeactivateTemplateState deactivateTemplateState) {
        return deactivateTemplateState.ordinal();
    }

    @Override
    protected DeactivateTemplateState getInitialState() {
        return DeactivateTemplateState.CONSTRUCT_BLACK_LIST;
    }

    public String getQueryId() {
        return queryId;
    }

    public Map<PartialPath, List<Template>> getTemplateSetInfo() {
        return templateSetInfo;
    }

    private void setTemplateSetInfo(Map<PartialPath, List<Template>> templateSetInfo) {
        this.templateSetInfo = templateSetInfo;
        prepareRequestMessage(templateSetInfo);
        prepareTimeSeriesPatternTree(templateSetInfo);
        prepareDataNodeRequest(templateSetInfo);
    }

    private void prepareRequestMessage(Map<PartialPath, List<Template>> templateSetInfo) {
        StringBuilder stringBuilder = new StringBuilder();
        stringBuilder.append("{");
        for (Map.Entry<PartialPath, List<Template>> entry : templateSetInfo.entrySet()) {
            stringBuilder
                    .append(entry.getKey())
                    .append(":")
                    .append(entry.getValue().stream().map(Template::getName).collect(Collectors.toList()))
                    .append(";");
        }
        stringBuilder.append("}");
        this.requestMessage = stringBuilder.toString();
    }

    private void prepareTimeSeriesPatternTree(Map<PartialPath, List<Template>> templateSetInfo) {
        PathPatternTree patternTree = new PathPatternTree();
        for (Map.Entry<PartialPath, List<Template>> entry : templateSetInfo.entrySet()) {
            for (Template template : entry.getValue()) {
                for (String measurement : template.getSchemaMap().keySet()) {
                    patternTree.appendPathPattern(entry.getKey().concatNode(measurement));
                }
            }
        }
        patternTree.constructTree();
        this.timeSeriesPatternTree = patternTree;
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        DataOutputStream dataOutputStream = new DataOutputStream(byteArrayOutputStream);
        try {
            patternTree.serialize(dataOutputStream);
        } catch (IOException ignored) {

        }
        this.timeSeriesPatternTreeBytes = ByteBuffer.wrap(byteArrayOutputStream.toByteArray());
    }

    private void prepareDataNodeRequest(Map<PartialPath, List<Template>> templateSetInfo) {
        Map<String, List<Integer>> dataNodeRequest = new HashMap<>();
        templateSetInfo.forEach(
                (k, v) ->
                        dataNodeRequest.put(
                                k.getFullPath(), v.stream().map(Template::getId).collect(Collectors.toList())));
        this.dataNodeRequest = dataNodeRequest;
    }

    @Override
    public void serialize(DataOutputStream stream) throws IOException {
        stream.writeShort(ProcedureType.DEACTIVATE_TEMPLATE_PROCEDURE.getTypeCode());
        super.serialize(stream);
        ReadWriteIOUtils.write(queryId, stream);
        ReadWriteIOUtils.write(templateSetInfo.size(), stream);
        for (Map.Entry<PartialPath, List<Template>> entry : templateSetInfo.entrySet()) {
            entry.getKey().serialize(stream);
            ReadWriteIOUtils.write(entry.getValue().size(), stream);
            for (Template template : entry.getValue()) {
                template.serialize(stream);
            }
        }
    }

    @Override
    public void deserialize(ByteBuffer byteBuffer) {
        super.deserialize(byteBuffer);
        queryId = ReadWriteIOUtils.readString(byteBuffer);
        int size = ReadWriteIOUtils.readInt(byteBuffer);
        Map<PartialPath, List<Template>> templateSetInfo = new HashMap<>();
        for (int i = 0; i < size; i++) {
            PartialPath pattern = (PartialPath) PathDeserializeUtil.deserialize(byteBuffer);
            int templateNum = ReadWriteIOUtils.readInt(byteBuffer);
            List<Template> templateList = new ArrayList<>(templateNum);
            for (int j = 0; j < templateNum; j++) {
                Template template = new Template();
                template.deserialize(byteBuffer);
                templateList.add(template);
            }
            templateSetInfo.put(pattern, templateList);
        }
        setTemplateSetInfo(templateSetInfo);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        DeactivateTemplateProcedure that = (DeactivateTemplateProcedure) o;
        return Objects.equals(queryId, that.queryId)
                && Objects.equals(templateSetInfo, that.templateSetInfo);
    }

    @Override
    public int hashCode() {
        return Objects.hash(queryId, templateSetInfo);
    }

    private abstract class DeactivateTemplateRegionTask<T> extends DataNodeRegionTask<T> {

        private final String taskName;

        DeactivateTemplateRegionTask(
                String taskName,
                ConfigNodeProcedureEnv env,
                Map<TConsensusGroupId, TRegionReplicaSet> targetSchemaRegionGroup) {
            super(env, targetSchemaRegionGroup, false);
            this.taskName = taskName;
        }

        DeactivateTemplateRegionTask(
                String taskName,
                ConfigNodeProcedureEnv env,
                Map<TConsensusGroupId, TRegionReplicaSet> targetSchemaRegionGroup,
                boolean executeOnAllReplicaset) {
            super(env, targetSchemaRegionGroup, executeOnAllReplicaset);
            this.taskName = taskName;
        }

        @Override
        protected boolean hasFailure() {
            return isFailed();
        }

        @Override
        protected void onExecutionFailure(TDataNodeLocation dataNodeLocation) {
            LOGGER.error(
                    "Failed to execute [{}] of deactivate template {} on {}",
                    taskName,
                    requestMessage,
                    dataNodeLocation);
            setFailure(
                    new ProcedureException(
                            new MetadataException(
                                    String.format(
                                            "Deactivate template of %s failed when [%s]", requestMessage, taskName))));
        }

        @Override
        protected void onAllReplicasetFailure(TConsensusGroupId consensusGroupId) {
            setFailure(
                    new ProcedureException(
                            new MetadataException(
                                    String.format(
                                            "Deactivate template of %s failed when [%s] because all replicaset of schemaRegion %s failed.",
                                            requestMessage, taskName, consensusGroupId.id))));
        }
    }
}
